1. Field of the Invention
The present invention relates to backlight modules, and particularly to a backlight module having a light reflecting and converging structure.
2. General Background
A liquid crystal display is capable of displaying a clear and sharp image through thousands or even millions of pixels that make up the complete image. The liquid crystal display has thus been applied to various electronic equipment in which messages or pictures need to be displayed, such as mobile phones and notebook computers. However, liquid crystal in the liquid crystal display does not itself emit light. Rather, the liquid crystal has to be lit up by a light source so as to clearly and sharply display text and images. The light source may be ambient light, or a backlight module attached to the liquid crystal display.
Referring to FIG. 5, a typical direct-type backlight module is shown. The backlight module 200 includes a frame 210, a linear light source 220, a reflective plate 230, and a diffusing plate 240. The frame 210 is substantially a rectangular box having a top opening (not labeled). The diffusing plate 240 is disposed corresponding to the opening of the frame 210, thereby forming a space for accommodating the reflective plate 230 and the light source 220. The frame 210 includes an inner bottom surface 214, and four inner side surfaces 212 substantially perpendicularly connected with the bottom surface 214. The light source 220 is supported by two opposite side surfaces 212, and is substantially parallel to the diffusing plate 240. The reflective plate 230 is disposed on the bottom surface 214 of the frame 210.
Some light beams emitting from the light source 220 directly reach the diffusing film 240, are diffused by the diffusing film 240, and emit out the direct-type backlight module 200. Other light beams emitting from the light source 220 reach the reflective plate 230, are reflected by the reflective plate 230, and finally emit from the diffusing plate 240.
However, some light beams emit obliquely from the light source 220, and obliquely enter peripheries of the diffusing plate 240. These light beams are liable to subsequently escape from the peripheries of the diffusing plate 240 and be lost altogether. As a result, the direct-type backlight module 200 may have a low light utilization ratio.
Therefore, a new direct-type backlight module that can overcome the above-described problems is desired.